


Shelter from my Storm

by NeitiHelvetti



Category: Assassination Classroom
Genre: Akabane Karma is a Good Friend, Alpha Akabane Karma, Alpha/Beta/Omega Dynamics, How NOT to deal with teenagers by Nagisa's mother, M/M, Mating Cycles/In Heat, Omega Shiota Nagisa, Pining, Possessive Behavior, Protective Akabane Karma, Shiota Nagisa Needs a Hug, Tags May Change, Thirsty Akabane Karma
Language: English
Status: In-Progress
Published: 2020-11-02
Updated: 2021-02-09
Packaged: 2021-03-08 18:15:09
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, Underage
Chapters: 4
Words: 6,770
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27331063
Author URL: https://archiveofourown.org/users/NeitiHelvetti/pseuds/NeitiHelvetti
Summary: Presenting might be the scariest event in Nagisa's life. Terrified of his mother he finds a safe place with Nagisa. How safe? Good question.
Relationships: Akabane Karma/Shiota Nagisa
Comments: 20
Kudos: 244
Collections: Mating Instincts





	1. Chapter 1

Nagisa's parents are betas. Most people are, it's the new traditional pairing as far as society is concerned. Alpha and Omega need special care, they sometimes act like animals and their special needs make them a liability to work with. There is something animal like about them, and it screws with their normal career and makes them untrustworthy.

That's what his mother says whenever the topic comes up.

It is what Nagisa is raised on, and it's only when he hits is second year of high school and around him his classmates start presenting and sexual education branches into gender education that he starts questioning it. 

Turns out that it's a lot more complicated than his mother has always made it out to be. And after a while Nagisa starts wondering if he really has a choice in all that. 

Gender education says no, nobody has a choice about their secondary gender. It comes in, sometimes early, sometimes late, but typically everyone presents by the time they're done with high school. Schools take it serious, give time off, offer counseling, mandatory gender education class, the works. But it's not until Nagisa is sitting down for dinner with his mother one evening that he realizes what that actually means. 

"-And of course HR has to give her those additional days off, because that bitch is in rut and can't control herself in a work environment! Now everybody has to suffer and make up for that and, Nagisa, honey, are you listening?"

"Yes mother, sorry mother", Nagisa looks up from his plate briefly and goes back to pushing around vegetables with his chopsticks. 

"Well, I'm sure she'll get what she deserves when she gets back! She does that every three months, if you can believe that. But management can't fire her for that, apparently the law-"

His mother prattles one and for a surreal moment Nagisa imagines what his mother would say if he presented as an alpha and took time off work for his ruts every three months. If he had to cope with instincts and whatever else he has learned about in class. It all sounds uncomfortable and a bit abstract for him. Would she- yes.

With a jolt Nagisa sits up straight. "I'm done, mother, may I be excused?"

"Go do your homework, honey, good girl."

He gets is books out and spreads them around but homework is the farthest thing on his mind tonight. If he presents as anything other than a beta, what would his mother do? She is barely holding it together with Nagisa wearing the male school uniform. Would presenting as an alpha be worse than a omega? She is always so spiteful about that one omega secretary at work...

There are shelters, he knows that. There had even been someone from an organization there for a day, talking about help phone lines and minor protecting acts and how to apply for welfare and free heat aids and other stuff. It had been a lot, and Nagisa had not been paying enough attention, because of course Nagisa would be a beta, how could he not?

Expect that the girl in his chemistry class was also from a beta family. She had presented as an omega last week. 

"What do I do?", he asks his math homework. It's as unhelpful as always. Math never gets easier, instead it simply introduces a new problem. Kinda like Nagisa's home situation. Expect that with math he knows he can ask for a tutor.

The next day brings more bad news for Nagisa. He feels anxious, and somehow he keeps rubbing his neck. It's not until someone makes a joke about growing balls (totally unrelated) that he starts noticing that something is wrong. 

His reflection shows him what he has been dreading: his neck is swelling. According to the text book that means his glands are developing and the has between two and seven days until his heat or rut manifests. Splashing cold water on his face and neck only makes his uniform wet.

His mother texts him to be ready for dinner with her and his dad tonight. She has chosen an expensive restaurant and she wants him to dress accordingly.

The pamphlet about presenting has very little actual advice, Nagisa finds while skipping his english class in the bathroom. It is very general and basically boils down to "your body is changing" and "it's going to be okay!" and the worst of them all: "talk to your parents or an adult you trust!" Nagisa has a shortage of adults he trusts in his life.

The internet is unhelpful, and full of weird porn. 

His teachers are out. He is technically a minor, so they would call is mother at some point and that's what he is trying to prevent. Even with the best intention he can't really see himself getting out of the situation without fighting is mother and-

With a shake of his head Nagisa forces himself to abandon that train of thought. Is father is out as well, as he is currently trying to build back a relationship with them. 

"Who else...", Nagisa wonders. "Trustworthy adult." He scrolls through his phone contacts. Oh. His finger hover over the contact, then he bravely calls. 

"Office, Karasuma speaking", a curt voice answers after a few rings. 

"Hi, it's Nagisa." His voice sounds high and breathy but still too loud in the school bathroom.

"Are you in danger?"

"What? No! Not right now." Nagisa gulps, it's no or never. "I need a favour."

"What is this about, Nagisa?" There are other voices in the background. Karasuma is probably busy at work. But if he gave out his work number then it's meant to be called, right?

"I need a safe place. And suppressants."

"Are you pregnant?", Karasuma asks, voice devoid of emotions. 

"N-no!" Nagisa yells "Not that! I'm presenting! My mother is going to kill me if she finds out. I just- I need somewhere to stay, and something to cover everything up."

"I'll call you back." 

The screen goes black and Nagisa is left staring at his phone. Was this good? Bad? How could he tell??

"Useless.", he tells himself and finally finds the energy to leave the bathroom. His mother is at work, so he sneaks off campus by jumping the wall at the back and makes his way home. He has a few hours before she shows up.

His phone dings and Nagisa dives for it with trembling hands. It's only a text from his mother.

"Meet me there, put on the green dress.", he reads aloud. The green dress is on his bed already, he notes with a bone deep sight. Of course. The dress is long, with a flowering skirt and a weird thing on the neckline. It falls on the floor in a puddle when Nagisa shoves it there. 

His neck feels swollen, his skin tight. His mother wants him to wear the green dress. Why is it so hot in his room? The dress is mocking him from the floor, the shiny green fabric laughing at him. He'd look like a kid playing dress up in that. 

Everything is a mess. Nagisa curls up on his bed and closes is eyes. Maybe if he shuts reality out? 

It does not work. 

He wakes up to a knock at his window, disorientated and feverish. For a moment he's not sure what is going on, thinks that maybe he is home with the flu, but then he stares at the green dress on the floor and-

The knocking gets louder. 

Nagisa jumps up and stumbles to the window. Stares out into the setting sun for a moment.

Oh shit.

What time is it? Did he miss dinner? His mother is- 

"Nagisa?"

Crouched down with his phone in his hands Nagisa wonders why his reaction time is so bad. He used to be better, faster. Less sluggish. There are missed calls and angry text from his mother. 

And Karma.

"What's up?", Karma asks as he climbs into the room. "You look sick."

"I- Karma! What are you doing here?"

The red head shrugs. "Sugino called me, something about trouble with your mom? Is she home?"

"Not yet.", Nagisa breaths out and sits back down on the bed. "Fuck."

"Wow, language." Karma sits down next to him and pokes the dress with his toe. He even took his shoes off, Nagisa notes. When did he do that?

"I don't well so good." 

"You look pale, did you eat something bad?"

But Karma's eyes are shrewed and the way he starts to look around the room shows that he is taking Nagisa serious. 

"'M presenting.", Nagisa mumbles. "Mom'll kill me when she finds out."

"That bitch", Karma says with a joyful smile that Nagisa knows from experience is not meant for joy. "C'mon, do you have a go bag?"

"What's a go- no, why would I have a go bag?"

"For emergencies, idiot." Karma rips open his wardrobe and starts tossing what he can grab into Nagisa's travel bag. "Can you get your toothbrush?"

Nagisa gets up and stumbles into the bathroom. He grabs what he uses, ignores the mirror and how pale he looks. Apparently he is taking too long. Karma comes to get him, stuffs everything into the bulging rucksack and drags him outside. Nagisa stumbles after him and into the night. 

When Karma gets the call from Sugino he is intrigued, but not worried. Sugino is working to the defense ministry in his off seasons to pay for his training, officially as a consultant on the team that dealt with the aftermath of Korosensei and- well, everything. But really, he had always been one of their PE teachers favorites and it showed. 

Paying a visit to Nagisa is hardly a hardship. They still live close enough.

It's convenient for stalking. Karma likes to make sure Nagisa is fine once in a while, likes to see the best assassin the country has to offer to go about his business without knowing that he's being watched. After their graduation (and everything else) Karma had been ready to give up on his pining for Nagisa, especially with their resident actress spending more and more time making moon eyes at Nagisa. Then they all went to different high school and now Nagisa never sees Karma, expect that Karma sees Nagisa and Nagisa has no idea. 

Some people talk to their crushes. Karma stalks his. 

He rings the doorbell, ready to face the strict woman who has given birth to the love of Karma's life. Nobody opens the door and Karma feels robbed of a fight. A quick look around shows that the door is not locked, which means that someone is home but not answering. 

Nagisa's bedroom is on the third floor, right above that one guy who is either an artist or a drug dealer. Breaking into that apartment is easy, from there he climbs up the building and knocks at Nagisa's window. The room is dark. 

He spots Nagisa on the bed, asleep in his uniform. For a moment Karma is tempted to settle down and simply watch but somehow he can tell something is wrong. Nagisa prefers lounge wear when he is home, not his uniform. 

He keeps knocking. Eventually, Nagisa opens. He is pale but sweaty. Keeps spacing out. Karma keeps himself from lecturing about the essential need of a go bag and starts packing. Nagisa is mostly useless, taking forever to round up his toothbrush and a few bathroom products. Luckily Karma is on it, and once they make it out the car is already waiting. 

The driver looks nervous. "Don't say anything, drive to the location given.", Karma instructs and turns arrange Nagisa to lie down with his head in Karma's lap. Karma can honestly not wait until he is allowed to legally drive. Thanks to Sugino he is aware that Karasuma likes to have junior agents trail him for training purposes, and usually it's fun, and their agreement is that Karma does no lasting damage and in turn gets a few favors. Like a car to take them to Karma's place without any evidence. 

"Hot", Nagisa mutters and Karma tries to sooth him while staring at the driver without blinking. Can't let the man think he can get away with anything.

Putting Nagisa in his bed includes carrying him up the stairs and Karma would like to say that he is too worried to enjoy the experience fully. He even restrains himself and only takes off the tie and loosens the shirt instead of stripping Nagisa down in his bed. 

Looking at the teenager burrowed in his bed Karma has a moment of clarity. 

It's been a few months since his own presentation. The process had been painful and annoying. He remembers clearly how much he had growled at everyone who came too close and how easy it was for him to lose his temper. It's the reason the house is empty tonight, his parents took off the moment it dawned to them that their estranged child was now a full blown alpha.

He calls Sugino once Nagisa looks settled. "He's presenting, I took him."

"Karma can I call you back?"

"Are you working?", Karma asks idly.

"I'm stuck in a vent, trying to shoot someone."

"Sounds fun. So, Nagisa is at my place, can you, I don't know, keep his mother from making a fuss? I can't fight her if I'm looking after Nagisa."

"You're a creep.", Sugino's voice is muffled. "I'll let someone know. Don't come running to me when he stabs you."

Karma is robbed of the opportunity of hanging up in Sugino, but overall that is not going to spoil is mood.

**Notes for the Chapter:**

> Please let me know what you think! 
> 
> No beta, not my first language, let me know if you spot any spelling mistakes or whatever
> 
> I've had this idea floating around for a while now but never got around writing it down but it keeps bugging me... which means I'm hella glad to get it done but that chapters are going to take forever, so be warned.


	2. Chapter 2

Nagisa feels hot. It is weird because his room has top notch air condition that his mother controls. He wakes up slowly. 

The room is not his room and it takes him a moment to place it at Karma's. Right. Because last night happened. For a moment Nagisa considers burrowing deeper into the mountain of blankets around him and hiding from reality. The blankets are warm and safe and smell nice. Excellent hiding spot.

"Are you going to stay in bed?"

Nagisa sits up at Karma's question. His friend is sitting on the edge of the bed. How long has he been sitting there? At Nagisa's wild look he only lifts the plate with omurice closer. 

"What."

"I made breakfast.", Karma explains, like that's the only thing Nagisa is unclear of.

"How did I get here?" The plate does look good, with something like a wonky devil drawn with ketchup on it. Nagisa takes is carefully. "How did you know-" he shrugs instead of putting everything in words. 

"Sugino called."

"Sugino?" Nagisa frowns and takes the first bite. Not bad. Suddenly he is ravenous. 

Karma looks pleased with his hunger. "He works for Karasuma in the off season. Said you called and needed help so I came to get you. Looks like you're in the middle of presenting."

Nagisa twitches at the nonchalant tone but keeps eating. 

"You can stay here until you get it figured out. My parents won't be back until next year."

"It's February."

"Exactly."

Nagisa hides his shiver at Karma's smug expression.

"I emailed your school to let them know you're taking the week of for presenting and they send a bunch of assignments. How did you manage to fail that PE run last year?"

"How do you know about that??"

Karma shrugs and keeps staring Nagisa down.

"Fine.", Nagisa looks away first and shoves his empty plate at Karma. "My mother hid my male uniform. I skipped. Happy?"

"Is she still doing that shit?" 

"Not anymore. I'm allowed to wear the male uniform but with the shorter tie because it's cuter. I'm going to pick up some extra credit so I can avoid swimming class this summer."

Karma is looking at Nagisa with a bland expression. Nagisa knows its artificial but he is not eager to start the whole discussion.

"Well. You can stay here, as I said." Karma gets up with the plate "There are towels in the bathroom, use whatever you want."

Then he gets up and leaves, muttering something about tie strangulation that Nagisa is pretending not to hear. He sinks back into the bed and tries very hard to not think about anything. Then he goes and takes a shower. His reflection is still pale, but better. The glands on his neck look swollen but not as red as before and they only feel sore and not painful when he gently prods them. 

The warm water sooth him for longer than he usually needs to shower. Somehow he can't picture Karma nagging him for it like his mother sometimes does. Weirdly enough his own soaps make him nauseous so he settles for a nondescript bottle that must be Karmas. Clean and feeling better about himself and the whole situation he marches back into Karma's room and straight out of it again. 

"I'm not naked", Karma informs him. Nagisa scowls, because half naked is not "not naked" in his opinion. 

He quickly finds his bags and rummages around for some loose joggers and a shirt. Thankfully Karma leaves the room, so Nagisa can freak out alone about how much he hates the thought of underwear right now. It takes him a moment to calm down from that.

"Do you have any weird urges? Want to smash something?", Karma asks later. Their homework is spread out on the dinning room table. 

Nagisa shrugs. Then he blushes when he remembers that he is in wearing underwear. "Nothing like that."

"Alright."

"Was that- I mean, did you do that? Smash things?"

Karma nods. "Yeah. Did a lot of running as well." 

"When did you present?" 

"Two months ago."

Nagisa nods like that is valid information that he needs. In truth he has no idea how he should be dealing with this. Can he ask questions? Is Karma an alpha or an omega? Usually only other alphas or omegas can tell by scent, most betas are left with assumptions. Does he want to ask? Imaging Karma as either takes Nagisa straight back to his gender education class and the part about the sex and suddenly he is feeling very warm.

"Any other hormonal urges yet?", Karma asks, his eyes piercing into Nagisa like he's reading his thoughts. 

"N-No! Nothing!"

Karma gives him a smirk like he knows that Nagisa is hiding his lack of underwear and goes back to his assignment without another word. Nagisa is left sweating and rubbing is legs together nervously. His homework is not getting the attention it needs, that's for sure.

Karma is keeping an eye of Nagisa. Nakamura would probably make fun of him because Karma cannot really remember if he had ever not kept an eye on Nagisa, but it is different now. For one, Nagisa is his guest and Karma is working with the flimsy excuse of caring for his guest's needs. Then there is his crush, which Nakamura has also called an obsession once or twice. And then there is the reality of Nagisa experiencing his first heat or rut.

Karma has always expected Nagisa to present as an alpha, if he ever did. As an beta he would be better suited to hiding in plain sight, which would work for Karma's theory that Nagisa is a natural born assassin. And he is strong, alphas are supposed to be macho strong and capable and Nagisa wins at strength in Karmas opinion.

If he is being honest he is looking forward to tussling with Nagisa. His own first rut had him picking a fight with everything, so this should be good. Maybe they can do some wrestling. They say alphas need to fight for dominance and Karma is so here for that.

He talks Nagisa out of leaving the house and convinces him to watch a movie with him. Once they are settled around the TV and Nagisa is paying more attention to the screen than Karma he leans in closer. His research suggests that another alphas smell, especially this close in his home, should rise his aggression and trigger his instincts. He has had a few tense moments in school and working on his self control is one thing. But usually? He knows what other alphas smell. They make his skin crawl. 

Nagisa smells good, honestly. A bit of Karma, which is nice. But otherwise there is something that reminds him of training outside during middle school, the smell of fresh sweat and sharp trees and something musky that rises from the earth. 

Karma is not a poet. He is, however, ready to lick up Nagisas neck to get more of that smell and maybe nibble at the throat a bit. Make that white skin bloom with a red mark-

He moves back with a jolt. 

Nagisa is not presenting as an alpha. Nope. Karma licks his lips. This is both better and worse than what he had expected.


	3. Chapter 3

**Summary for the Chapter:**

> Nagisa is worries, until he doesn't. Karma is Up To No Good (and also somewhat creepy).

**Notes for the Chapter:**

> The last bit is a bit creepy. I'm considering adding a tag for it, but I'm unsure which one. Let me know if you have any thought about it. Maybe non-con touching? I'm going to have to chance them later on because there will be Other Stuff as the story develops.. Might as well start now and save a few innocent readers from getting invested..

His mother calls the school and they try calling him. 

Nagisa knows, because she sends him enough texts to flag a memory storage warning.

"Do you want to answer?", Karma asks. They are sitting at the dinning table with their dinner half eaten on top of some school books. Nagisas phone keeps vibrating and announcing call after call.

Nagisa shakes his head. 

Karma makes a grab for the phone while holding the water pitcher and Nagisa saves his phone by tossing it towards the couch.

"Suit yourself.", Karma mutters at Nagisas dark look. "The school knows that you're presenting so they won't do anything until next week. Legally, they can't. Illegally, they can't because I told Karasuma to make sure."

"You what? Karma!"

"Don't look so mad, do you want the school to call the police? Underage student goes missing before heat, they might actually show up."

With a huff Nagisa gets up. "I don't even- How are you so calm with this all?"

Karma smiles cheerfully. 

"Don't answer. Ugh, what am I going to do? My mother pays my tuition, she's going to pull me out- I can't be a homeless high school dropout!"

"Okay, no. You're not homeless, you're staying here." Karma even looks a bit mad so Nagisa meekly agrees to that. It would be rude not to, right? Mollified Karma tries to reassure Nagisa further: "You can always access the 3E fund. Rob a bank, I'll help. We can live in the park together if you want to. Or apply for a scholar ship. Most schools have them."

Nagisa shakes his head. "I won't touch that money. And my school has none." 

"Are you sure?" Karma is already on his phone, looking it up. "Okay, you're right. Bummer. I bet- Let me look up their board of directors real quick."

"Karma, stop!"

"Oh look! That guy looks shifty, look at him!"

Nagisa is dragged over to Karma and stares down at the phone. "He- I don't know-"

"It's the eyes, Nagisa!", Karma insists. 

The man looks normal enough to Nagisa, a bit sweaty maybe, but nice enough. Looks can be deceiving and Karma can be stubborn so he only shrugs. 

"Finish your math paper, I'm going to figure it out!"

Nagisa watches Karma get an old laptop out and start tapping away, merrily humming. With a huff he stares down at his homework. Right. Better get it done. Karma will take care of everything else, he just needs to- What a weird thought.

Later during dinner Naigsa feels off kilter. Somehow his skin feels itchy, like when he first stopped the daily work outs after graduation and his body was aching for movement. But just thinking of going outside for a run makes him shiver. He can't. 

"More pepper?", Karma asks, still pilling oily peppers from a jar into his rice. 

Nagisa shakes his head and stares down at his own rice and fish. Maybe he can do a work out later? Karma should have some weights or something, they could do it together. Maybe get sweaty and- Oh. 

"Everything okay?"

Karma's golden eyes stare into him and freeze Nagisa in his seat. 

Does he know what Nagisa is thinking and how he wants and needs, how his body is pushing for movement and something else, something very specific. Karmas eyes bore into Nagisa and he smirks and Nagisa wants to bite him and make him never take his stupid eyes off Nagisa-

His chopsticks fall onto the table with an echoing clatter. "I'm done!", Nagisa croaks, voice high and throat dry. "Thank you for the food!"

"You barely ate anything.", Karma remarks. 

"Yes, I'm sick, sorry." He rushes into the kitchen, face flushed. Still, he can't throw the food away, just hides it in the fridge. After all Karma made it for him. Cleaning the kitchen helps with the itchiness somewhat. Not totally. He sneaks up the stairs before Karma can catch him. 

On the bed are his bags, but there are also Karmas blanked and his pillow, and an extra plush blanked that looks really soft. It is not even a conscious thought that has Nagisa pushing the bags from the bed and draping himself into the blanked. It smells fantastic and it's as soft as it looked. 

For a moment, its enough. 

\--------------------------

He has to restrain himself from humming when he skips up the stairs. Watching Nagisa during dinner had been delightful. Even better, he had gotten the first sniff of true omega scent. It had been faint. But by now it was unmistakably an omega scent. 

A happy, horny omega. 

That is curled up on his bed, apparently.

Nagisa blinks up at him, like he is not sure how he got to where he is now. 

With a smirk Karma turns and goes to gather as many blankets and sheets as he can. He dumps them on the bed and starts arranging them around Nagisa. The soft scent flares, flooding the bedroom with moist earth and something utterly addictive. The omega looks sleepy and lethargic, only following Karma around the room lazily. 

Karma listens to a soft whine when he leaves to brush his teeth and can't help his grin. His crush is finally where he wants him. Going into heat and in his den.

During the night Nagisa keeps moving and kicking and it takes until nearly morning that Karma rolls on top off him and holds him down with his weight. From then, it's even better. The soft omega smell lures Karma into a deep, dreamless sleep. 

Sadly it makes Nagisa twitchy for the whole morning but Karma has a plan. After breakfast and watching Nagisa start tidying one thing and abandoning it shortly for something else to clean up for a while, he drags him out off the house.

Nagisa covers his neck with those delicious smelling scent glands with a fluffy scarf. Karma won't argue, since it's his scarf and makes him smell even more like him. There is something satisfying about the way Nagisa follows him obedient until they board the train into the city.

"Where are we going?"

"Where do you wanna go?"

"Karma!"

"You need to seize the day more, Nagisa. It's healthy." Nagisa gives him a flat look. Like he knows that Karma read that on a pamphlet meant for his elderly neighbor. "We are going to visit a new friend!"

"Karma why"

"C'mon, this is our stop. I want a snack, do you want anything?" Karma grabs Nagisa's hand and tugs him with him, out off the train and into the small store at the train station. Nagisa nearly bumps into the narrow display of matcha flavored canned soda.

"I want tea", Nagisa decides. Tea is safe. Safer than whatever Karma has planned. 

After they buy tea, weird soda and an unholy amount of snacks Karma shows Nagisa a small park. It's surprisingly nice to sit on a beach and share their bounty.

"This is false advertisement", Karma grouses, hot chips in one hand. "They're lucky I'm not in the mood for legal actions."

"What are you in the mood for, then?"

Karma grins. 

Nagisa takes another sip of his tea. He can wait. 

"Blackmail.", Karma finally relents. He offers Nagisa some candy. 

"Blackmail.", Nagisa echoes. "Who are you blackmailing?"

"We.", Karma corrects and looks pleased when Nagisa finally takes the candy. 

"I'm not blackmailing anyone."

"Not alone, no."

"Why are we doing this right now? I have homework!"

"Exactly. Now watch me solve your problems."

Nagisa leans back and watches Karma get up and walk towards one of the families clustered around the playground. He talks to them for a bit, points back at Nagisa and even bows. Nagisa is too lazy to go check up on them. Besides, if his past friendship with Karma has taught him anything it's that he should choose his battles wisely. And that it takes a lot of energy to stop Karma. 

"Did you get what you wanted?", he asks once Karma comes back.

The red head hums and swipes some candy from Nagisa. 

"Can we go home, then?"

"Why? Are we out of snacks already?"

"I want a nap. I don't trust you to carry me." He does, kind of. No need to tell Karma that. Although he looks like he already knows. Nevertheless he helps Nagisa pack up their snacks and they make their way back to the train station.

If Nagisa falls asleep on Karma during the ride back, lets just say that Nagisa is never mentioning it and that makes it less real. No need to tempt fate and ask if Karma took pictures.

\--------------------------

Karma breaths in Nagisa's soft omega smell. While on the train he had had to stare down quite a few challenging alphas, with Nagisa's smell soft and inviting and waving through the carriage. But now that they where back in Karma's room the smell was more intense. Nagisa had gone straight to the bathroom and emerged with wet hair and soft pajamas. 

They did talk a lot about personal space and how dens and nests where sacred places in school, and while Karma had taken that information it had never really been related to him. Expect now. Because now Nagisa was moving around his den in his sleep, cuddled in blankets and pillows.

Nagisa whines softly in his sleep. Karma blinks down at him, trying not to move as not to spook the omega. 

But the omega only turn around and borrows deeper in the blanket that Karma usually sleeps with. 

He is well aware how creepy it is to watch someone sleep. During his most obsessed observations- stalking, perhaps- he had refrained from watching his target sleep, mostly out of convenience. And because Nagisa had really thick curtains that where always closed. Seeing him now, vulnerable and trusting, is a rush for Karma. 

He could do anything.

Fascinated he slowly caresses the side of Nagisa's head. His hair is still damp from the shower earlier. He rubs it. it's soft. 

His forehead is warm. It's almost textbook for an omega to run an higher temperature during their heat. And, if Karma's sex ed textbook is to be believed, he should be sleeping a lot once he feels safe. Once the nest is satisfactory the Omega will sleep until hungry and horny, but during their very first heat they will most likely not experience the horny part in all it's glory. 

Karma has seen the porn, a full on omega heat looks exhausting. 

He softly shakes Nagisa to make sure he is really out of it. His guest does not stir. Even a hand on his newly developed glands only triggers a soft moan. 

(It takes Karma a full minute to unfreeze after that.)

Softly humming the sets up the baby monitor he keeps deep in his closet and then goes downstairs for a thorough meal prep. His omega is going to be hungry once he wakes up and Karma is fully committed to providing. 

He's not going to let Nagisa slip away. That's his omega.

**Notes for the Chapter:**

> Please let me know if you have any ideas for tags, I mostly add them as I go but that might not always be the best way to tag :P


	4. Chapter 4

An omegas first heat can last between mere hours and a week, but it's typically between two and five days. The first heat is the easiest one, that's what Karma has been taught. It's referred to as a "puppy heat" and mating an omega during it is frowned upon. Most omegas stay home for a week, sleep a lot and make their parents feed them. Nagisa sleeps a lot, which is textbook, and he eats whatever Karma makes him, but he also cuddles a lot.

Karma spends a lot of time researching omega biology on his phone while Nagisa sleeps. The internet is a wild place, with a lot of information different than what he had been taught in school. There is a lot of weird material online, and a ton of porn, too. But a few parenting blogs indicate that the cuddling suggests a strong bond and trust.

It's adorable, Karma finds, but he is fully aware how biased he is. Nagisa is currently curled up, his face pressed into Karmas side, purring softy once in a while.

For Karma, this is heaven. The soft puff of breath, the sweet smell that is mixing with his own alpha musk. He is pretty sure that Nagisa would never be this compliant and let Karma arrange him as he wants and how he wants if awake. 

With a content sigh Nagisa burrows deeper into Karma, pressing his full body against him. Karma gently strokes over the blue hair as the omega shuffles around. 

"Are you uncomfortable, Nagisa?", he asks with a soft coo, "what's wrong?"

Nagisa throws one leg over Karma's and that's when Karma realizes what is going on. The omega is hard, rutting against him, groaning softly. The parenting blogs did not mention this.

"Are you awake?", he asks, making sure to keep his voice even. The omega reacts to his voice, but does not open his eyes. Only moans and ruts, and Karma is very much aware of his weakness. 

Maybe his intentions are good when he caresses down Nagisas back, but that changes soon enough. Nagisa is pliant against him, softly pressing into him and humming when Karmas fingers dip under the elastic of his pajama pants. Soft skin greets him, hot to the touch. He can't stop touching, can't hold back a groan when Nagisas scent spikes. 

"Did you know that I wanted to ask you out in middle school? But Kayano got there first, and you somehow turned her down before she could confess properly. Rio still laughs about that, did you know? I had to fight her for you later, she cracked my ribs but I won because you are mine."

Karma gets no verbal answer. Nagisa twitches hard in his arms, moving his head up and when his breath hits Karmas scent glands on his neck he feels like he has been hit by lightning. This is it, in a way. This is how he wants Nagisa, soft and trusting, with his hips trusting into his tight. 

It takes him only a second to glance at his morals, then his hand goes down the pants and finds Nagisas hard dick. The angle is weird, but Karma is making it work. Nagisa presses closer, lips scraping over Karma's neck, and his hands clutching his shirt. 

"I got you, Nagisa.", Karma whispers. Gently he toys with the slit, listening closely to Nagisa's soft moans. There is a lot of moisture, pre and sweat and Karma groans when he realizes that it might also be slick- Nagisa moves. Karma freezes for a moment, but then Nagisa only moves closer, almost climbs on top of Karma. It cramps his hand harder but then it works better and with only a few strokes Nagisa moans and shutters. He keens as he comes, breath heating up Karma's neck, clutching closer to Karma, now stiff as a board. Karma is panting softy and trying to stay still. He longs to drag Nagisa over him properly and push his own pants down and- With a muttered curse he pushes Nagisa off him and flees to the bathroom. He knew things would get weird and complicated, but he had not counted on it testing everything he has. 

His heat wasn't as bad as he feared. It's mostly hazy, Nagisa thinks. He owes Karma, he thinks sluggishly as he sinks deeper into the warm water. He feels content and the warm bath is lulling his musings back into the fog. Weirdly enough he can tell that Karma has been taking care of him and it fills him with smug satisfaction.

It's a bit scary. 

His omega instincts don't care about the distance Nagisa has been keeping between himself and Karma. There are no salty feelings for not texting, only memories of cuddling and holding tight.

Nagisa dunks his head under the water to escape his thoughts. It does not help, only makes his lungs burn after a while. Not worth it, he decides. He is not going to hide away! He is a natural assassin, retired or not, and he is not going to-

"Are you hungry?", Karma asks from the door and Nagisa squeaks in surprise. "I can order something."

"Not hungry!"

"Yeah, I'm going to pick up some food from down the road, they make everything fresh so I might be a while. Take your time."

Nagisa nods, waves him off and is done with his bath the moment he hears the front door close behind Karma. He scrambles out of the tub and towels off hurriedly. Nagisa might be a bit paranoid, but he had been once taught that everyone has their secrets and Nagisa is very interested in Karma's secrets. 

Karma's bed room is tidy enough, with the bed resembling a mountain of bedding, but ignoring his nest -oh right, his nest- but otherwise it's tidy. There are a few text books on the desk, but Nagisa starts with the wardrobe. Karma has no shame, his uniforms are hanging innocently next to a box labeled "rut aid". Nagisa's first impulse is to shove the box back in but he finds his resolve somehow and opens the box. There are bottles of lube, scent patches, dirty magazines and a few sex toys. They did learn in middle school that hiding your secret in plain sight works sometimes, but if you are hiding something let them find something first. The box might be like that, he thinks. 

Otherwise the wardrobe yields nothing more interesting than Karma's old middle school PE uniform which Nagisa suspects is actually rather new since it looks like it might fit Karma right now. There is not a single weapon which makes Nagisa suspect that there must be another hiding place. 

The bookcase is next. Nagisa learns that Karma has questionable taste in many things, but nothing truly weird. The desk only hosts school work and their old middle school picture, which is sweet, and there is nothing under the bed. He finds what he is looking for in the linen cupboard in the hallway. Sewn into a ugly red pillow case are five knifes, two guns and ammunition. He recognizes the gun models with a nostalgic smile.

Happy that he has found the stash he is carefully folding the garish pillow case back around the weapons when he sees another, even uglier sheet. Under it sits a brown folder. Hastily he snags the folder but before he can even open it he hears the door and Karma's greeting from downstairs. The folder goes under his shirt and then later gets taped under the wardrobe while Karma is in the bathroom. Nagisa would have to wait for some privacy to complete his snooping. 

Over their take out they discuss Karma's school and somehow Karma has produced a letter of acceptance from the vice principal. It's the middle of the school year, Nagisa does not remember applying. He's too tried to ask. Maybe he is also afraid of Karma's answer. His intensity is hard to take sometimes and Nagisa is still tired from his first heat. 

Going to bed should be awkward. But Nagisa crawls into his nest while Karma is in the bathroom and falls asleep before he can wonder if Karma would join him in his bed if he asked. It already smells like them both, so it would not be too strange, Nagisa thinks and steps seamlessly into a dream. 

**Notes for the Chapter:**

> Sorry it's a short and late chapter, this took forever and has been blocking me from getting the rest done. Surprisingly three jobs will steal all your time and energy, what a discovery! Next chapter is nearly done and this work is growing for some reason into something bigger. Idk,let's see.


End file.
